The present invention relates to an apparatus for composite plating the inner surface of a cylindrical body such as an engine cylinder, etc.
There have been proposed a plurality of kinds of updraft flow apparatuses for composite plating the inner surface of a cylindrical body, wherein a rod shaped electrode is inserted in the cylindrical body, composite plating liquid, comprising plating liquid containing metallic ions and fine particles of antiabrasion materials, lubricants, etc. dispersed in the plating liquid, is made to flow upward in the annular space between the rod shaped electrode and the inner surface of the cylindrical body, and electric power is applied between the rod shaped electrode and the cylindrical body to composite plate the inner surface of the cylindrical body. An example of a conventional composite plating apparatus is shown in FIG. 3.
In the conventional updraft flow apparatuses for composite plating the inner surface of a cylindrical body, the maximum current density is practically restricted to about 20 A/dm.sup.2 because circumferential distribution of the flow velocity of the composite plating liquid in the annular space is uneven and the increase of the current density causes defects in appearance, such as burning, rough deposits, lack of plating, flaking, flowering, etc. Thus, the productivity of the composite plating work with the conventional updraft flow apparatuses for composite plating the inner surface of a cylindrical body is low.